The invention herein described relates generally to polymeric compositions for forming optical waveguides and methods for forming such optical waveguides using the same. In particular, the present invention relates to polymers made from at least one cyclic olefin monomer which can be used to form optical waveguides using either a clad-first or core first technique.
The demand for continuous increase in transmission speed, data capacity and data density in integrated optical and optoelectronic circuits has been the motivating force behind numerous innovations in areas of broadband communications, high-capacity information storage, and large screen and portable information display. Although glass optical fibers are routinely used for high-speed data transfer over long distances, they are inconvenient for complex high-density circuitry because of their high density, poor durability and high cost of fabrication for complex photonic circuits. As such, polymeric materials hold great promise for constructing cost effective, reliable, passive and active integrated components capable of performing the required functions for integrated optics.
The present invention relates generally to polymeric compositions for forming optical waveguides and methods for forming such optical waveguides using the same. In particular, the present invention relates to polymers made from at least one cyclic olefin monomer which can be used to form optical waveguides using either a clad-first or core first technique.
In one embodiment, the present invention relates to polycyclic polymer compositions formed from one or more monomers or oligomers represented by the following structure: 
wherein each Xxe2x80x2xe2x80x3 independently represents oxygen, nitrogen, sulfur, or a methylene group of the formula xe2x80x94(CH2)nxe2x80x2xe2x80x94 where nxe2x80x2 is an integer of 1 to 5; xe2x80x9caxe2x80x9d represents a single or double bond; R1 to R4 independently represent a hydrogen, a hydrocarbyl, or a functional substituent; and m is an integer from 0 to 5, with the proviso that when xe2x80x9caxe2x80x9d is a double bond one of R1, R2 and one of R3, R4 are not present.
In another embodiment, R1 to R4 independently comprises a hydrocarbyl, a halogenated hydrocarbyl or a perhalogenated hydrocarbyl group which are selected from: i) linear or branched C1-C10 alkyl groups; ii) linear or branched C2-C10 alkenyl groups; iii) linear or branched C2-C10 alkynyl groups; iv) C4-C12 cycloalkyl groups; v) C4-C12 cycloalkenyl groups; vi) C6-C12 aryl groups; and vii) C7-C24 aralkyl groups, provided that at least one of R1 to R4 is a hydrocarbyl group.
In another embodiment, one or more of R1 to R4 represent a functional substituent independently selected from xe2x80x94(CH2)nxe2x80x94CH(CF3)2xe2x80x94Oxe2x80x94Si(Me)3, xe2x80x94(CH2)nxe2x80x94CH(CF3)2xe2x80x94Oxe2x80x94CH2xe2x80x94Oxe2x80x94CH3, xe2x80x94(CH2)nxe2x80x94CH(CF3)2xe2x80x94Oxe2x80x94C(O)xe2x80x94Oxe2x80x94C(CH3), xe2x80x94(CH2)nxe2x80x94C(CF3)2xe2x80x94OH, xe2x80x94(CH2)nC(O)NH2, xe2x80x94(CH2)nC(O)Cl, xe2x80x94(CH2)nC(O)OR5, xe2x80x94(CH2)nxe2x80x94OR5, xe2x80x94(CH2)nxe2x80x94OC(O)R5, xe2x80x94(CH2)nxe2x80x94C(O)R5, xe2x80x94(CH2)nxe2x80x94OC(O)OR5, xe2x80x94(CH2)nSi(R5)3, xe2x80x94(CH2)nSi(OR5)3, xe2x80x94(CH2)nxe2x80x94Oxe2x80x94Si(R5)3, and xe2x80x94(CH2)nC(O)OR6 where in independently represents an integer from 0 to 10, R5 independetyl represents a hydrogen, a linear or branched C1-C20 alkyl group, a linear or branched C1-C20 halogenated or perhalogenated alkyl group, a linear or branched C2-C10 alkenyl group, a linear or branched C2-C10 alkynyl group, a C5-C12 cycloalkyl group, a C6-C14 aryl group, a C6-C14 halogenated or perhalogenated aryl group and a C7-C24 aralkyl group; and R6 is selected from xe2x80x94C(CH3)3, xe2x80x94Si(CH3)3, xe2x80x94CH(R7)OCH2CH3, xe2x80x94CH(R7)OC(CH3)3 or one of the following cyclic groups: 
or one of the following: 
wherein R7 represents a hydrogen or a linear or branched (C1-C5) alkyl group.
In still another embodiment, a polymer composition in accordance with the present invention is formed from one or more monomers or oligomers as described herein in combination with one or more crosslinking agents. Furthermore, in still another embodiment, the one or more crosslinking agents are latent crosslinking agents.
In one embodiment, the at least one crosslinking agent can be the compound shown below: 
In yet another embodiment, the one or more crosslinking agents are represented by one or more of the following structures: 
In yet another embodiment, the present invention relates to polycyclic polymer compositions formed from one or more monomers or oligomers represented by the following structure: 
wherein each Xxe2x80x2xe2x80x3 independently represents oxygen, nitrogen, sulfur, or a methylene group of the formula xe2x80x94(CH2)nxe2x80x2xe2x80x94 where nxe2x80x2 is an integer of 1 to 5; Q represents an oxygen atom or the group N(R8); R8 is selected from hydrogen, a halogen, a linear or branched C1-C10 alkyl, and C6-C18 aryl; and m is an integer from 0 to 5.
In yet another embodiment, a polycyclic polymer composition formed from one or more monomers represented by the following structure: 
wherein Xxe2x80x2xe2x80x3 represents oxygen, nitrogen, sulfur, or a methylene group of the formula xe2x80x94(CH2)nxe2x80x2xe2x80x94 where nxe2x80x2 is an integer of 1 to 5; RD is deuterium, xe2x80x9cixe2x80x9d is an integer ranging from 0 to 6, with the proviso that when xe2x80x9cixe2x80x9d is 0, at least one of R1D and R2Dmust be present; R1 and R2 independently represent a hydrogen, a hydrocarbyl, or a functional substituent; and R1D and R2D, which are optional, independently represent a deuterium atom or a deuterium enriched hydrocarbyl group containing at least one deuterium atom.
In another embodiment, a polymer composition for use in a waveguide is produced from one or more monomers or oligomers described.
In still another embodiment, a polymer composition according to the present invention further includes at least one crosslinking agent. In one embodiment, the crosslinking agent is a latent crosslinking agent.
The present invention is advantageous in that it provides polymer compositions which permit the formation of optical waveguides having better performance qualities such as, for example, a difference (xcex94n) in the refractive index of the core material versus that of the clad material of at least about 0.00075 (i.e., at least about 0.05% where the clad or cladding material has a refractive index of about 1.5) for over a broad wavelength range (e.g., about 400 to about 1600 nm); lower intrinsic optical loss (lower than about 1 dB/cm and in some cases lower than about 0.5 dB/cm); a high glass transition temperature (Tg) (e.g., in one embodiment at least about 150xc2x0 C., in another embodiment at least about 250xc2x0 C., and in some cases at least about 280xc2x0 C.).
Additionally, the present invention is advantageous in that it provides core and/or cladding compositions which can have a low viscosity or viscosities so as to be deliverable by any suitable technique, including ink jet printers, screen printers or stencil printers. Furthermore, the disclosed core-first method for forming optical waveguides is advantageous in that it permits the formation of optical waveguides with a reduction and/or elimination in the occurrence of xe2x80x9cswellingxe2x80x9d between layers (see FIGS. 5A and 5B for a photographic depiction of xe2x80x9cswellingxe2x80x9d). Thus, the core-first method permits the formation of improved waveguides.
The foregoing and other features of the invention are hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawings setting forth in detail one or more illustrative embodiments of the invention, such being indicative, however, of but one or a few of the various ways in which the principles of the invention may be employed.